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Discussion Starter #1
Alright my timing chain jumped a tooth, got the cams at 12 and 10 with 20 pins between at TDC, put the tensioner back in, and started to turn the crank by hand to see if the timing was going to maintain.... then POP! The 2 pieces that hold the rocker arm flew out of the valvetrain after about 3/4 of a turn and the rocker arm is out, but NOT BROKEN?!?! WTF Does anyone know why this happened and what I need to do to fix it?









 

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i try!
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did you have the shim and the guide mixed up? that would cause the rocker arm to come off!
 

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Discussion Starter #4
There was only 19 pins between the sprocket marks and I couldn't time my car past 2 degrees, I am 100% sure I jumped a tooth, thats not the problem now, I didn't not TOUCH the rocker arms so I couldn't have mixed anything up?!?! I am VERY CONFUSED!
 

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damn that sucks, same thing happened to a friend of mine.

if you want a used rocker, theres a guy parting out his rr motor in classified, check the mechanical section, I think his username is b15nismo
 

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Discussion Starter #6
Thanks, I need to get one, Does anyone know how this could have happened? I mean I was turning the crank by hand, I'm baffled
 

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4-door sr action
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those just sit on there they don't actually hold the rocker arm, you can just unbolt the cam and slip the rocker arm back in
 

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wants 2 dry hump chriscar
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those just sit on there they don't actually hold the rocker arm, you can just unbolt the cam and slip the rocker arm back in
exactly, they just pivot on the cam and the valve. those things that poped off are the shims.......peices of carefully measured metal that that keep the valve train from "ticking"

Greddy Rocker Arm Stoppers, allow you to rev higher than stock without risk of kicking off rocker arms. A common problem on SR20's. A finger rests above each of the eight rocker arms if they've began to float and raise then they hit the finger and this keeps them from coming off their seat and causing catastrophic engine failure.
^ get some. cost about$40-70 on ebay

when you jumped a tooth the rocker most likely shifted and when the cam turned that was enough to push it off its seat......causing the valve springs to decompress shotting the shims accross the room.:biggthump
 

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Discussion Starter #9
Really, so if the arm isn't cracked or broken I could just put it back in? Do you need to get a new shim and guide, or can you re-use the ones that popped out? I haven't taken the cam out again since it happened.
 

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SR powered S13 coupe
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Really, so if the arm isn't cracked or broken I could just put it back in? Do you need to get a new shim and guide, or can you re-use the ones that popped out? I haven't taken the cam out again since it happened.
Put them back in...

The issue is, what caused the binding and rocker to pop off, are you sure that you didn't skip more than a few teeth? I guess you can carefully try to turn the motor over again and see if it happens yet again. If it does, then you got a bigger problem to worry about.

Also, don't get the rocker arm stoppers... don't take my word for it, just do a search on the forum and you'll find alot of credible guys that will steer you away from using them.
 

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wants 2 dry hump chriscar
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Put them back in...

The issue is, what caused the binding and rocker to pop off, are you sure that you didn't skip more than a few teeth? I guess you can carefully try to turn the motor over again and see if it happens yet again. If it does, then you got a bigger problem to worry about.

Also, don't get the rocker arm stoppers... don't take my word for it, just do a search on the forum and you'll find alot of credible guys that will steer you away from using them.
you think its possible the reason the rocker jumped or shifted is because a valve taped?
 

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SR powered S13 coupe
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you think its possible the reason the rocker jumped or shifted is because a valve taped?
He corrected for the links between the sprokets, but if his crank is off now... and there is no easy way to check this that I know of with the motor in the car. Then yes its possible he smacked a valve to the piston causing the bind and rocker to pop out. This is just my wild guess though...
 

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merely a flesh wound
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and there is no easy way to check this that I know of with the motor in the car
Stick a long screwdriver down the #1 spark plug hole and slowly turn the crank until #1 is at TDC. When it's there, the timing pointer should be lined up with the 0 degree mark on the crank. I say "should", because I've seen instances where the outer ring of the stock crank pulley has rotated relative to the inner portion, so you can't always rely on the timing marks.

C
 

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Discussion Starter #15
I'll try to put it back in and manually crank it hopefully it doesn't pop out again. The only way to tell if the crank is off is by pulling the head and cover, right? That would suck, this is fun:(
 

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Broke Ass
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I'll try to put it back in and manually crank it hopefully it doesn't pop out again. The only way to tell if the crank is off is by pulling the head and cover, right? That would suck, this is fun:(
Just have to pull the front cover and match up the timing marks if all else fails.
 

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SR20DE stock G20 p10 highport
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Pulling the front cover involves FIRST removing the crossmember, the exhaust from the manifold, the upper and lower oil pans, the crank pulley, the alternator, radiator (to pull the alternator more easily) and the power steering and a/c, alternator belts. A lot of bolts.
 
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